Fire-box door for steam-boilers.



A. G. ELVIN. FIRE BOX 13003 FOR STEAM BOILERS.

APPLICATION FILED FEB. 5, 1907.

Patented July 1, 1913.

2 BH'EETFSHBET 1.

wnulsslsw am mail.

A. e. BLVIN. FIRE BOX DOOR FOB STEAK BOILERS.

APPLIOATIOK FILED FEB. 5, 190? Patented July 1, 1913.

2 SHEETS-SHEET 2.

WITNESSES ALBERT G. ELVIN, OF FRANKLIN, PENNSYLVANIA.

FIRE-BOX DOOR FOR STEAM-BOILERS.

Specification of Letters Patent.

Patented July 1 1913.

an Application filed February 5, 1907. Serial No. 855,877.

To all whomit may concern Be it known that I, ALBERT G. ELviN, ofFrunklimin the county of Venango' and State of Pennsylvania, haveinvented a certain new and useful Improvement in Fire- Box Doors forSteam-Boilers,' of which improvement the following is a description.

The object of my invention is to provide a firebox door which shall beof simple, inexpensive, and durable Construction and ready adaptabilityin connection-with steam boilers of the locomotiveand other standardtypes, and which may be operated either manually or by power as desired,and by the application of Which,lab0r in tiring and consumption of fuelmay be substantially re duced, and deterioration of boiler flues andother parts incident to the use'of doors of the ordinary construction beprevented.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings: Figure 1 is, a front View, in elevation,of a firebox doorappliance', illustrating an application of myinvention; Fig. 2, a view, partly in front elevation and partly insection, of the same; Fig. 3, a vertical section through the,

salne'and through the adjoining portion of the rear water wall of asteam. boiler; Fig. 4, a vertical central section, on an enlarged Scale,through the lower portion of the cylinder and its lower head, showingthe operating valve as unseated for the supply of fluid tofithe piston;Fig. 5, a similar view, showing the operating valve as seated for theexhaust of fluid from the piston; Fig. 6, a horizontal section throughthe cylinder and piston; and, Fig.7, a vertical section, on an enlargedscale, through the lower poition of the cylinder and its lower head,taken at right angles to Figs. 4 and 5.

In the practice of my invention, I secure to the rear water Wall, 1, ofa locomotive .or other steam boiler, surrounding the firing opening, 2,thereof, a door frame, 3, which is of substantially rectangular form,and provided with lugsflt, which abut against the water wall, 1, and areslotted horizontally to inclose studs 5, fixed in said wall, to whichthe door frame is firmly connected by nuts, 5, engaging threads on saidstuds. 'Ihe longitudinal horizontal slots of the lugs enable the studs,5, to he set -in such positions in the water will as to be clear of staybolts therein. central opening is formed in thedoor frame and anoperncndcd throat or casing, 7, corresponding substantially in contourwith, and surrounding-the firing opening, is formed around said cen tralopening, on the inner side of thedoor frame, said throat abutting at itsend farther from the door frame, against the water wall, and a shovelingplate, 8, pro: jects from thedoor frame into the firing opening, toprotect the firebox sheets from injury by blows from the firemansshovel. An oil cantray, 3, is connected to the top of the door frame,and affords a convenient support for oil cans &c.

An upper door section, 9, and a lower door section, 9*, each of which isa hollow or chambered casting of substantially rectangular form, arefitted to slide vertically in guides, 10, bolted to the sides of thedoor frame, the door sections fitting accurately on their abutting edgeswhenclosed, and the joint between them being preferably formed on anincline as shown in Fig. 3. The space within the lower section is openat its top and bottom, and that within the ing, 7. The interior of thedoor sections 1 thus forms anair space, through which, when they areclosed, air is drawninto the firebox, and in which the air is highlyheated before passing into the firebox,.with the resultant advantages ofprotecting the door sections from becoming too hot and being therebysoon warped or burned out, and of promoting combustion and preventingthe formation of smoke, furnishing a supply of heated air to the gasesevolved from; the combustion of the fuel in the firebox. The uppersection is made heavier than the lower, in order to assist in closing.

The door sections, 9, 9, are moved from and toward each other, to openand close, respectively, the outer end of the throat or casing, 7, bymeans of levers, 19,, 12, pivoted by pins'or bolts, 13, to one side ofthe farther from the arms, 14, 14 and an op-. crating handle, 18, isfor-medon the outer end of one of the arms, as the n per arm, '14, bythe movement of whic handle,

through the engagement of the curved slots,

foot of the fireman, if'desired.

- with'a piston, 28, provided with suitable In order to enable the doorsections to be held at their maximum distance apart,

so as to expose the jentire'o ening of the throat, 7, as when cleanlng are, or to partially expose said opening, as for admitting air above thegrates when itis desired to. check the draft through the boiler tubes, alatch shaft, 19, is journaled in a bearing, 20, on the-side of the doorframe opposite that to which the levers, 12, 12*, are pivoted, saidshaft carrying, on one of its ends, a latch, 21', adapted to engage oneof a set of hooks or'projectio-ns 22, on the upper door section, 9, andcarrying, on its opposite end, an operating handle, 23, which may bethrown back against a stop, 24:, on

the door frame, to hold the latch in such position that it cannot engagethe'hooks during ordinary firing or'during such periods as it is notdesired to keep the door sections at a greater or less distance apart.

The construction above described affords desirable facilities forquickly and conveniently effecting the opening and closure, either totalorpartial, of the throat, 7, as required in the operations of firing,cleaning fires, or checking draft, as well as for protecting themovable, door sections from injury by the heat of the-firebox and foraffording a supply of heated air above the grate. To further facilitatethe effective performance of its functions, it is, however, preferablysupplemented by means for operating the door sections by fluid pressure,as air or steam, and a construction for this purpose, which has beenfound in practice to be advantageously operative, is herein exem lifiedand will-now be described.

vertical fluid pressure operatin' cylinder, 25, is bolted 'to the sideof ,t e door frame, 3, which adjoins the segment gears, 17, 17, of thedoor section levers, and is closed at its upper and lower ends by heads,

26, 27. The cylinder, 25, is cut away on its side next the segmentgears, so as to allow them to project-into it, and is fitted packingrings, 29, near its lower end. A longitudinal recess is'formed in .thepiston,

' 28, above its packing rings, and provided with a rack or plurality ofteeth, 39, engaging the teeth of the segment gear, 17, of the lower doorsection. V Upward unevement is imparted to the piston by fluid pressure,which is preferably compressed air, admitted to its lower end through asupply The supply and exhaust of motive fluid to and from the piston areeffected by an operating valve, 33, which is of the lift or puppet type,and is fitted to move horizontally 111 a chamber, 34, in the lowercylinerating valve therein, are constantly exposed to the fluid pressurein the supplf pipe, the operating valve being, consequently, niiirmallyheld seated by said pressure The operating valve is formed on or fixedto a eylinolricat site-n1, 35, which projeets outwardly through acorresponding bore in the lower cylinder head, in the di* rection of thedoor frame, and abuts against a downwardly projecting arm, 36, on a rockshaft, 3?. journaled on said frame. The rock shaft, 37, carries ahorizontally proice-ting arm, 38, which bears against one arm of adouble armed lever, 39, journaled on a pin, i fixed in the door framebelow the lower door section, andthe opposite arm of said lever isconnected to the inner arm of a double ari'ned treadle lever, 41,journaled (n the lower portion of the door frame. The'outer arm of thetreadle lever is bent downwardly to a level slightly above that of thedeck or firing floor of the boiler,

and carries a treadle, 42. By downward pressure of his foot upon thetreadle, 42, the fireman can, through the lever system above described,unseat the o crating valve, and; upon the release of sue pressure, thevalve will he reseated by the pressure from the supply pipe acting uponit in its cham ber,

A central supply passage, 43, is formed in the valve stem, 35,, saidpassage communicating by radial ports, 44, with the valve chamber, 34,when the operating valve is unseate d, and extending to radial ports,45, leading into an annular peripheral groove or channel 46, in thevalve stem. In all positions oi the operating valve and stem, thechannel, 46, registers with a main supply and exhaust port, 47, leadingthrough the lower head, 27, into the cylinder, 25, and,

.nary exhaust passage, 49, is formed in the wall of the cylinder, saidpassage opening thereinto by a port, 50, located slightly below thelevel of the bottom of the piston, 28.

when at. the upper extremity of its traverse, and, the lower end of thepreliminary exhaustpassage opens into the cy-hndncal the door sectionsapart or der head, 27, which chamber, and the op;

bore in which the valve stem, 35, works, at such a oint in the lengththereof as to register with the channel, 46, of said stem, and,through'said channel, with the final exhaustport, 48, when the operatingvalve is seated. The area for traverse of fluid through the port, 47, ismadeless than thatthrough the preliminary exhaust passage, and isvaried, as desired, by a regulating valve, 51', formed on the'end of anadjusting screw, 52, en gaging a thread in the lower head, by themovement of which screw, the valve, 51, may be caused to close the port,47, either entirely or to any desired degree.

In the operation of theappliance, when not fitted with a power actuatingmecha nism, or in the event of the derangement of such mechanism, thedesired movement, either total or partial, of the door sections,

. is effected by the fireman by application of hand pressure to thehandle, 18, or foot. pressure to the tread, S)". The door sectionsaresubstantially balanced, and can therefore be moved more easily andconveniently than doors of the ordinary type.

W'hen utilizing a power actuating mechanism, substantially as described,the fireman places his foot on the treadle, 42, and there by depressesthe outer end of the lever, 41,

which, through the lever, 39, and rock shaft, I

37, and its arms, transmits the applied pressure to the stem, 35,0f theoperatingvalve, 33, and unseats said valve. Operating fluid is therebyadmitted to the cylinder, 25, below its piston, 28, through the ports,44, passage, 43, ports, 45, peripheral channel, 46, and port, 47, thepressure of the fluid raising the piston to the limit of its upwardtraverse, in which, through the gearing and door sections, it moves thedoor sections away from one another the limit of their traverse, andfully opens or uncovers the firing throat channel, 7. Said channel re-.mainsopen only so long as the pressure of the firemans foot ismaintained on the treadle, and, upon the release of this pressure, theoperating valve is immediately seated by the pressure in its chamber,34. The upper end port, 50, of the preliminary exhaust passage, '49,'haspreviously been uncovered by the piston passing above it, and

the lower end of said passage has, by the seating of, the operatingvalve, been brought into communication with the channel, 46, and finalexhaust port, 48.. The port 47, is

alsoopento the channel, 46, and final exhaust port, 48. The operatingliuid is therefore exhausted from the cylinder, and the piston is forceddown by the spring, 32,

bringing the door sections to their normal closed position insitsdownward moi-'ement. The preliminary exhaust being open before thepiston commences'its downward stroke, the larger portion of theoperating fluid below the piston will be immediately released,

thereby allowing the door sections to be quickly started in theirclosing movement,] and as the port, 50, is closed by the piston inpassing it, the remainder of thedownward stroke of the piston and theresultant movement of the door sections will be'made more slowly, owingto the comparatively restricted discharge opening, through the port, 47,as regulated by the valve, 51. The piston will be thus, in a substantialdegree, cushioned, so that while the door sections start to closequickly, they will come together easily and without shock.

The construction of the appliance is such as to involve comparativelyfew working parts, and these are of such character that they can besubstantially made and are protected from liability to breakage and fromdamage by the access of dirt, The operation of the door sections, eitherby the power of the fireman or by fluid pressure, is quick, simple, andeasy, and the automatic closure of the door sections when'the fluidpressure i'nechanisin is used, effects the substantial advantage ofcompelling single shovel tiring, the advantage of which practice, inecontunizing fuel, perfecting combustion, and reducing firebox and fluerepairs, has been universally recognized in railroad service. Thebenefit of the supply of hot air afforded by the hollow door sections isa further advantage attained in the application of the improvement. i 1

I claim as my invention and desire to secure by Letters Patent:

1. In a fire box door appliance,'the com binat-io-n of a supportingframe adapted for connection to a steam boiler fire-box and having anopening of dimensions and contonr proper to surround a fire boxdoor'opening, vertically sliding upper and lower hollow or chambered doorsections, the lower section having a passage for the admission of air tothe chambered door sections and the upper section having an opening forthe discharge of air into the furnace, said door sections being tittedto traverse on the door frame in direction to cover and uncover theopening therein, and means for simultaneously moving Said door sectionsin opposite directions. v

2. In a tire box doo-r'appliance, the combination of a supporting frameadapted for taneously moving said door section-sin opposite directions.

3. In a fire box door appliance, the combination of a supporting frameadapted for connection to a steam boiler fire-box, an open ended throator channel projecting from said frame and adapted to surround a fire boxdoor opening, a shoveling plate projecting from the frame above thebottom of the throat o-r channel and extending beyond the inner endthereof, vertically sliding upper and lower normally abutting hollowdoor sec tions fitted to traverse on the frame in direction to cover anduncover the outer end of the throat or channel, the lower section havinga passage for the admission of air to the hollow door sections and theupper section having an opening for the discharge of air into thefurnace, and means for simultaneously moving said door sections inopposite directions.

4. In a fire box door ap liance, the combination of a supporting rameadapted'for connection to a steam boiler fire-box, an open ended throator channel projecting from said frame and adapted to surround a firebo'x' door opening, lugs projecting from the frame above'and below thethroat or channel and provided with longitudinal slots for the receptionof studs to secure the frame to the tire box, verticallysliding upperand lower normally abuttin hollow door sections fitted to traverse on teframe in direction to, cover and uncover the outer end of the throat orchannel, the lower section having a passage for the admission of air tothe hollow door sections and the upper section having an opening for thedischarge of air into the. furnace, and means for simultaneously movingsaid door sections in opposite directions.

5. In a firebox door appliance, the combination of a supporting frameadapted for connection to a steam boiler fire-box, and having an openingof dimensions and contour pro-per to surround a firebox d or opening,two hollow or chambered door sections, each having passages for theadmission and discharge of air, said door sections being fitted totraverse on the door frame in direction to cover and un over the openingtherein, two levers, each pivoted to the door frame on one side of adoor section and having a curved slot. adjoining its free end, pinsfixed to the door sections and engaging the slots of the levers,intermeshing gears fixed on the levers concentrically with their pivotsand meansfor operating one of the said gears.

6. In a firebox door appliance, the combination of a supporting frameadapted for connection to a Steam boiler fire-box, an open ended, throator channel projecting from saidfiinme and adapted to surrounda fireboxdoor opening, two ho-rmally abutting door sections fitted to traverse onsaid frame each pivoted to the door frame on one side of a door sectionand having a curved'slot adjoining its free end, pins fixed to the doorsections and engaging the slots of the levers, intermeshing gears fixedto the levers concentrically with their pivots, and means for operatingone of said gears.

7. In a tire box door appliance, the combination of a supporting frameadapted for connection to a steam boiler fire-box and having an openingof dimensions and contour proper to surround a fire box door opening,vertically sliding upper and lower normally abutting hollow doorsections fitted to traverse on said frame in direction to cover anduncover the opening therein, the lower section having a passage for theadmission of air to the hollow door sections and the upper sectionhaving an opening for the discharge of air into the furnace, mechanismfor simultaneously moving said door sections in opposite directions, anda fluid pressure device'connected with and actuating sa-id mechanism.

8. In a tire boxdoor appliance, the combination of a supporting frameadapted for connection to a steam boiler fire-box, and having an openingof dimensions and contour proper to surround a fire box door opening,vertically sliding upper and lower hollow or chambered door sections,the lower section having a passage for the admission of air to thechambered door sections and the upper section having an opening for thedischarge of air into the furnace,

said door sections being fitted to traverse on the door frame indirection to cover and uncover the opening therein, mechanism forsimultaneously moving said door sections in opposite directions, and afluid pressure d evice connected with and actuating said mechanism.

In a fire box door appliance, the combination of a supporting frame forconnec tion to a steam boiler fire-box, an open ended throat or channelprojecting from said frame and adapted to surround a fire box dooropening, vertically sliding upper and lower normally abutting hollowdoor sections fitted to traverse on said frame in direction to cover anduncover the outer end of said throat or channel, the'lower sectionhaving a passage for the admission of air to the holelow door sectionsand the upper section having anopening for the discharge of air into thefurnace, mechanism for simultaneously moving-said door sectionsinopposite directions,-and a fluid pressure device connected with andactuating said mechanism.

1.0. In a tire box door appliance, thecom bination of a supporting frameadapted for connection to a steam boiler fire-box, and

having'an opening of dimensions and con- .tour proper to surround afirebox door opening, movable upper and lower normally abutting hollowdoor sections fitted to traverse on said frame in direction to cover anduncover the opening therein, the lower sec tion having a passage for theadmission of air to the hollow' door sections and the upper sectionhaving an opening for the discharge of I air into the furnace, twolevers, each pivoted to the door frame on'one side of a door section andhaving a curved slot adjoin- 11. In a fire box door appliance, the com-I bination of a supporting frame adapted forconnection to a steam boilerfire box and having an opening of dimens ons and contour proper tosurround a fire box door opening, vertically sliding upper and lowernormally abutting hollow door sections fitted to traverse on said framein direction to cover and uncover the opening therein, the lower sectionhaving a passage for the admission of air to the hollow door section andthe uppersection having an opening for: the

discharge of air into the furnace, mecha 'nism for simultaneously movingsaid door sections in opposite directions, a fluid pressure cylinder, apiston working therein and actuating the door section moving mechanism,an operating valve controlling the supply and exhaust of fluid to andfrom said piston, and a spring bearing on said pistonand acting toeffectits traverse in direction opposite to that effectedby the actionof fluid pressure.

12. In a fire box door appliance, the combination of a supporting frameadapted for connection to a steam boiler fire-box and having an openingof dimensions and con- Q and, when seated, exhausts fluid pressure tourproper to surround a fire box door opening, vertically sliding upper andlower normally abutting hollow door sections fitted to traverse on saidframe in direction to:

therefrom, and which is continuously sub ject to fluidsupply pressure, alever system for unseating the operating valve, and

by fluid pressure to exhaust lower normally abutting hollow a springbearing on the piston and acting to effect its traverse in directionopposite to that effected by the action of fluid pressure, l3. in a firebox door appliance, the combination of a supporting frame adapted forconnection to a steam boiler fire box and having an openingof-dimensions and con-- tour proper to surround a fire box door opening, verticallysliding upper and lowernormally abutting hollow door sections r fittedto traverse on said frame in direction. to coverand uncover the openingtherein, and the lower section having a passage for the admission of airto 'the hollow door sections and the upper section having an opening forthe discharge of air into the furnace,

.meclia nisinfor simultaneously moving saiddoor sections in opposite.directions, a fluid pressure cylinder, a piston working therein andactuating the door section moving mechanism, an operatin valve which,'when-unseated, ad'mits fluid pressure to the piston,- and, when seated,exhausts fluid pressure therefrom, and which is continuously snbject tofluid supply pressure, alever system, one member of which contacts withthe operating valve, means, as a treadle, for'unsea-ting the operatingwho through the lever system, and a spring bearing on the piston andacting, when the operating valve is unseated, to effect the-traverse ofthe piston in direction opposite to that effected by the. action offluid pressure.

14. In a fire box door appliance, the cornbination'of a supporting frameadapted for connection to a steam boiler fire-box and having an openingof dimensions and contour proper to surround a fire box door opening,vertically sliding upper and lower normally abutting hollow doorsections fitted to traverse on said frame in direction to cover anduncover the opening therein, and the lower section having a passage for;

the admission of 'air to the hollow door sec tions and the upper sectionhaving an i ing for the discharge of air into the furnace,

mechanism for simultaneously moving said j 7 door sections in oppos tedirections, a fiunl pressure cylinder having-aj direct supply andexhaust port, a piston lwdrking therein and actuating the door sectionmoving mechanism, a preliminary exhaust port leading into thecylinderadjacent to the limit oftraverse of the piston, a final exhaust'port, anoperating valve controlling all of'said ports and continuously subjectedto fluid supply pressure, and means for unseating the operating valvetoadmit fluid pressure to the piston and permitting it to be reseatedfluid pressure froni'the piston.- 15. Ina fire box doorappliance, thecombination of vertically sliding up er and cor sec tions, and thelowensectionhaving a pas-- bination of vertically sliding upper andl0W('I normally abutting hollow door sec-- tions, and the lower sectionhaving a pas sage for the admission of air to the hollow door sectionsand the upper section having an opening for the discharge of air intothe furnace, mechanism for simultaneously moving said door sections inopposite directions, a fluid pressure cylinder, a piston Working thereinand actuating the door section moving mechanism, an automaticallyseating operating valve controlling the supply and exhaust of fluid toand from the piston, an adjustable regulating valve interposed betweenthe operating valve and the piston, and means for unseating theoperating valve.

17. In a tire box door appliance, the combination of vertically slidingup r and lower normally ahutting hollow oor sections, and the lowersection having a passage for the admission of air to the hollow doorsections and the upper section having an opening for the di arge of airinto the furnace, mechanism for simultaneously mov ing said doorsections in opposite directions, a fluid pro ire cy inder, a pistonWorking therein and actuating the door section moving mechanism, anautomatically seating operating valve controlling, when unseated, thesupply of fluid to the piston for effecting its movement in opening thedoor sections, and controlling, when seated, the free exer sectionhaving haust f fluid from the piston st the beginning of its movementcoincident with the closure of the door sections, and a comparativelyrestricted exhaust of fluid during the remainder of its movementin thesame direction, and means for unseating said oper' ating valve.

18. In a firebox door appliance, the combination of vertically movableupper and lower normally abutting hollow door sec tions, the lowersection havir g a passage for the admission of air to the hollow doorsections and the upper section having an opening for the discharge ofair-into the furnace,

mechanism for simultaneously moving said door sections in oppositedirections, a fluid pressurocylinder, a piston Working therein andactuating ,the door section moving mechanism, a tread closing one end ofthe cylinder, and provided with an operating valve chamber and acylindrical bore for an Operating valve stem, a fluid supply pipeleading into the valve chamber, a main supply and exhaust port leadingfrom the cy- 7o lindrical bore into the end of the cylinder, apreliminary exhaust port leading from said bore into the cylinderin aplane adjacent to the limit of outward traverse of the piston, a finalexhaust port leading from said here. to the atmosphere, an operatingvalve adapted to seat in the valve chamber at the inner end of saidbore, a stem fixed to said valve and fitting in and passing through saidbore, and having a peripheral groove or channel adapted to register withthe ports aforesaid, a longitudinal passage in said stem having radialports at its ends leading to the periphery of the stem adjacent to thevalve and to the radial groove or channel, respectively, and means forunseating the operating valve.

ALBERT Gr. ELVIN,

lVitnesses:

B. A. KRENZ, F. WV. MAR'rIn.

